Professionalism merges the individual into patterns of total environment. Amateurism seeks the development of the total awareness of the individual and the critical awareness of the groundrules of society. The amateur can afford to lose. The professional tends to classify and specialise, to accept uncritically the groundrules of the environment. The groundrules provided by the mass response of his colleagues serve as a pervasive environment of which he is contentedly unaware. The 'expert' is the man who stays put.
Marshall McLuhan, Quentin Fiore, Jerome Agel (1996). “The medium is the massage: an inventory of effects”, Hardwired